There has been proposed a vehicle headlight including a laser light source and a wavelength converting member as well as a safety device, for example, those disclosed in Japanese Patent Application Laid-Open No. 2011-066069 (or US2011/0063115A1 corresponding to the Japanese laid-open publication). The vehicle headlight can project light obtained by wavelength-converting the original laser light from the laser light source by means of the wavelength converting member. In this vehicle headlight, there arises a problem in which the wavelength converting member is damaged, so that the laser light can erroneously exit through the damaged area to the outside. To cope with this problem, the vehicle headlight can include the safety device. The safety device can include a light detector configured to detect laser light intensity. The safety device can be configured to compare the output from the light detector with a reference value to suppress the output of the laser light on the basis of the comparison result.
In the above-described conventional art, the safety device is applied to the vehicle headlight being of a reflector type having a paraboloidal reflector. In view of this, there further arises a problem in which the safety device cannot be properly applied to a lighting unit having a lens member that can control light from a wavelength converting member, which can receive laser light for wavelength-converting the laser light, i.e., when the wavelength converting member is damaged, the lighting unit cannot properly prevent the erroneous emission of laser light from the lens member through its light emission surface to the outside even with the safety device.